Variable levels of carry over on platelet counts < or = 20 x 10(9)/l with the Bayer Advia 120

Accurate platelet counts are essential for the safe management of severe thrombocytopenia (platelet counts < or = 20 x 10(9)/l). The effect of carry over on platelet counting in severe thrombocytopenia was investigated by performing counts before and after saline rinses on three Bayer Advia 120 automated blood counters. Counts were performed in both primary and manual closed tube system modes on two instruments and in manual open tube mode on a third. A total of 194 samples with platelet counts < or = 20 x 10(9)/l were studied. First counts were significantly higher in all groups. The magnitude of the difference varied both by analyser and counting mode. Carry over was minimal with one analyser in primary mode and second counts were on average only 5.5% lower; on a second analyser in manual closed tube system mode second counts were on average 37.7% lower. A first count of > or = 10 x 10(9)/l fell to <10 x 10(9)/l on the second count in 35 of 145 samples (24.1%). In five such samples, all tested on one analyser, the second count was <50% of the value of the first count. Two of 49 (4.1%) first counts of <10 x 10(9)/l increased to > or = 10 x 10(9)/l on repeat. These results show a variable and often potentially clinically important carry-over effect on severely thrombocytopenic samples using the Advia 120.     

Immunoplatelet counting: potential for reducing the use of platelet transfusions through more accurate platelet counting

Research is required to determine the optimal approach for prophylactic platelet transfusions in patients with haematological malignant disorders. It has been suggested that thresholds for prophylactic platelet transfusions of platelet counts below 10 x 109/l should be investigated, as these may be equivalent in clinical effectiveness and associated with lower costs and fewer complications. An important concern in such investigation is the accurate estimation of platelet counts below 10 x 109/l. This study aimed to further examine the potential reduction in platelet usage that could be made if a lowered platelet transfusion threshold of 5 x 109/l was used in conjunction with an immunoplatelet counting method. Clinical and laboratory data from 130 haematology patients were used. Standard platelet counting was performed using Bayer H3 and ABX Argos analysers. Immunoplatelet counting was performed by flow cytometry using anti-CD61. The potential for reducing platelet transfusions included consideration of clinical criteria that influence prophylactic platelet transfusion use. The results indicated that the use of an immunoplatelet count with a 5 x 109/l platelet transfusion threshold would potentially reduce the number of transfusions by 10.4% in comparison with a 10 x 109/l threshold and standard automated platelet counting with the ABX Argos analyser, and increase the number of transfusions by 5.4% in comparison with the same threshold using the Bayer H3 analyser. The immunoplatelet count may aid the clinical decision to transfuse platelets, but would not necessarily lead to a reduced use of platelet transfusions.     

Analysis of outcome of laparoscopic splenectomy for idiopathic thrombocytopenic purpura by platelet count

Laparoscopic splenectomy (LS) is now performed routinely in patients with idiopathic thrombocytopenic purpura (ITP) refractory to the medical treatment. Low preoperative platelet count was deemed to be a contraindication for a laparoscopic approach; however, there is no data reporting the outcome in those patients. We aimed to evaluate the influence of the preoperative platelet count on the operative and postoperative course and complication rate. Retrospective cohort study that was conducted in tertiary care university-affiliated medical center and included 110 consecutive patients who underwent LS. All patients were divided into three groups by their preoperative platelet counts: 50 x 10(9)/L (n = 80). The outcome and the influence of preoperative factors predictive of complications, blood transfusion, and length of stay were compared between the groups. Patients with a platelet count of 20 x 10(9)/L before surgery. Patients with counts >20 x 10(9)/L can safely undergo LS.     

High-dose dexamethasone for splenectomy in patients with idiopathic thrombocytopenic purpura.

High-dose intravenous immune globulin (IV IgG) is currently the treatment of choice for patients with idiopathic thrombocytopenic purpura (ITP) who undergo splenectomy; however, this treatment is extremely expensive. We report on 13 ITP patients with severe thrombocytopenia (<20 x 10(9)/l) who were prepared for laparoscopic splenectomy with a 4-day oral course of high-dose (40 mg/day) dexamethasone (DEX). Four patients had an excellent response with platelet counts that increased to above 150 x 10(9)/l. Seven patients had a good response with a platelet count that increased to between 50 and 150 x 10(9)/l (median 121 x 10(9)/l). Two patients were resistant both to DEX and IV IgG. The operation was uneventful in all the patients, including the 2 who had resistant ITP and were operated on while their platelet count was very low (5 x 10(9)/l). Thus, high-dose DEX, which is an easy, effective and inexpensive treatment, is recommended for the preparation of ITP patients prior to splenectomy.     

Effect of eradication of Helicobacter pylori on platelet recovery in patients with chronic idiopathic thrombocytopenic purpura: a controlled trial

Several recent studies have suggested that an association exists between Helicobacter pylori (HP) eradication and improvement in platelet count in a significant proportion of patients with idiopathic thrombocytopenic purpura (ITP). In this controlled study, we prospectively examined adult patients with chronic ITP for HP infection, and assessed the effect of HP eradication on platelet count. One hundred forty-two consecutive Iranian patients with chronic ITP were assessed. Those who met the criteria and had platelet counts >30 x 10(9)/L within the medication-free screening month were enrolled (n = 129; 66 females; mean age, 29.2 +/- 7.0 years). HP-positive patients received a 2-week course of triple HP eradication therapy (i.e., amoxicillin, clarithromycin, and omeprazole) and were followed for 48 weeks. An ITP response was defined as a platelet count of >100 x 10(9)/L 24 weeks after treatment, together with an increase in the platelet count >30 x 10(9)/L over the baseline value. HP infection was detected in 79 (61%) patients. HP-positive patients were significantly older than HP-negative subjects (P = 0.018). HP eradication was successful in 87% (62/71) of those who completed the eradication therapy. Whereas 48% (30/62) of HP-eradicated patients showed an ITP response, no HP-negative patient had an ITP response. The ITP response persisted for 48 weeks in 93% (28/30) of the responders. The ITP responders had a shorter disease duration than the nonresponders (P = 0.002). The management of mild-to-moderate chronic ITP in Iranian patients, especially those with a recent onset of disease, should include an investigation for and eradication of infection with HP.     

Platelet count evaluation using three automated haematology analysers compared with the immunoplatelet reference method, and estimation of possible inadequate platelet transfusion

The accuracy of three automated haematology analysers [Sysmex XE-2100 (both optical and impedance mode), Bayer Advia 120, and Beckman Coulter LH-750] was compared with the immunoplatelet reference method for platelet measurement. A total of 165 blood specimens were obtained from patients and platelet counts were determined using the four-automated haematology analyser methods and the immunoplatelet reference method. The coefficients of determination (R(2)) between the automated haematology analyser methods and the immunoplatelet reference method for the overall platelet range were >0.98. A bias study, however, showed some disagreement. The use of a coincidence correction calculation for the immunoplatelet method did not improve the correlation between the immunoplatelet method and the automated haematology analyser methods. To estimate the possibility of inadequate platelet transfusion, the number of prophylactic platelet transfusion indications determined by the automated haematology analyser platelet counts were compared with the number of transfusion indications according to the platelet counts determined by the immunoplatelet method. An additional 48 blood specimens were included in this analysis. All of the automated haematology analysers showed some disagreement in the transfusion indications when compared with the immunoplatelet method, suggesting the possibility of inadequate platelet transfusion.     

Patterns of platelet response in idiopathic TTP/HUS: frequency of declining platelet counts with plasma exchange and the recognition and significance of a pseudo refractory state

For thrombotic thrombocytopenic purpura (TTP), daily plasma exchange (TPE) is typically discontinued when the platelet count normalizes (>150 x 10(9)/L). We observed a decline in platelet count during TPE and in patients who appeared pseudo-refractory because of a platelet count plateau (100-150 10(9)/L range). In the present study, we evaluated platelet count trends in TTP patients. Retrospective review of TTP patients from 01/1999 to 12/2004 was completed. Patients were categorized based on platelet count trends: Group I, counts rose then decreased to levels <100 x 10(9)/L; Group II, counts declined following TPE initiation; Group III, counts rose continuously; Group IV, counts decreased after the count was >100 x 10(9)/L. Additionally, we identified pseudo-refractory patients caused by a platelet count plateau (>100 x 10(9)/L but <150 x 10(9)/L). We identified 60 TTP patients. Within Group I (17 patients/17 series/19.1% of total), the mean decrease in platelet count was 67.3% +/- 22.1% following initial rise. Within Group II (24 patients/25 series/28.1% of total), the mean decrease was 28% +/- 5.3% following presentation. Group III included 31 patients/39 series (43.8% of the total). Within Group IV (seven patients/eight series/9.0% of total), the mean decrease was 17.4% +/- 12.6% following a sustained rise >100 x 10(9)/L. With a declining platelet count and daily TPE, it is generally sufficient to stay the course and the decline will reverse. Our limited experience with pseudo-refractory patients supports discontinuing TPE when counts plateau between 100 and 150 x 10(9)/L when a therapy goal is a platelet count of 150 x 10(9)/L. Recognition of this pseudo-refractory state can minimize the risks of prolonged TPE and the risks of adjunct interventions.     

Efficacy of Helicobacter pylori eradication in raising platelet count in adult patients with idiopathic thrombocytopenic purpura

BACKGROUND AND OBJECTIVES: There are data consistent with an association between idiopathic thrombocytopenic purpura (ITP) and Helicobacter pylori (HP) infection. In addition, a significant increase of platelet count following HP eradication has been reported in a proportion of ITP patients. We describe here our experience on the efficacy of anti-HP treatment in ITP patients. DESIGN AND METHODS: Between December 1998 and May 2001 sixteen adult patients with ITP and documented HP infection were treated with standard antibiotic therapy for HP eradication (amoxicillin and clarithromycin plus pantoprazole combination). Of these patients, 7 had untreated ITP with mild/moderate thrombocytopenia (median platelet count 70x10(9)/L, range 41-91), 5 had relapsed following a previous steroid treatment (median platelet count 39x10(9)/L, range 30-90) and 4 were refractory to steroids (median platelet count 18.5x10(9)/L, range 9-30). RESULTS: An improvement of platelet count was observed in 11/15 patients (73.3%) who achieved HP eradication. The difference between the mean platelet count SD before and after HP eradication was statistically significant (51.6 28.2x10(9)/L vs. 143.3 131.1x10(9)/L; p=0.01). Complete or partial responses were obtained in 11/16 treated patients (68.7%). This result still persisted after a median follow-up of 11.7 months. INTERPRETATION AND CONCLUSIONS: Our data confirm the efficacy of Helicobacter pylori eradication in increasing platelet count in adult ITP patients.     

Successful treatment with vincristine for an elderly patient with idiopathic thrombocytopenic purpura]

A 77-year-old female was referred to our hospital in March 1991 because of a severe bleeding tendency. Her blood count on admission was as follows: Hb 7.5 g/dl, WBC 4.6 x 10(9)/l with normal differentiation and platelet 2 x 10(9)/l. One month prior to admission, her blood count was normal. Initially, acute idiopathic thrombocytopenic purpura (ITP) was suspected, because of the acute onset of the bleeding tendency and thrombocytopenia. High dose intravenous immunoglobulin (400 mg/kg/day for 5 days) and bolus methylprednisolone (1 g/day for 3 days then tapered) were administered, starting March 13. Her platelet count had increased immediately on March 20 to 40 x 10(9)/l. However, platelet count decreased to 4 x 10(9)/l in the following two weeks. Her clinical course differed from that of typical acute ITP. Because the treatment with prednisolone was not effective, it was changed to intravenous infusion of vincristine (VCR) at a weekly dose of 1 mg for 6 weeks. The treatment was extremely effective, and her platelet count reached over 200 x 10(9)/l. The treatment was discontinued. Three weeks later, her platelet count decreased to 15 x 10(9)/l, the administration of VCR was resumed, and her platelet count recovered again. Throughout her clinical course, no side effect of VCR was noticed except for mild hypesthesia of the fingertips. VCR therapy was considered to be an useful treatment in elderly patients with ITP.     

The frequency of bleeding complications in patients with haematological malignancy following the introduction of a stringent prophylactic platelet transfusion policy

Indications for platelet transfusion remain controversial and are frequently based on arbitrary numerical criteria. In October 2000, we introduced a stringent prophylactic-platelet transfusion policy < 10 x 109/l for stable patients and < 20 x 10(9)/l in the presence of major bleeding or additional risk factors. A trigger of < 50 x 10(9)/l was introduced for patients undergoing invasive procedures. A prospective analysis was performed measuring the frequency of minor and major bleeding events, morbidity, mortality and duration of pancytopenia. Blood product usage was assessed and health care savings measured. A total of 98 patients were evaluated on 2147 patient study days and 271 bleeding episodes were recorded. Major bleeding occurred on 1.39% (30/2147) of the study days when platelet counts were < 10 x 10(9)/l and 2.3% (50/2147) of the study days when platelet counts were 10-20 x 10(9)/l. In patients with platelets > 20 x 10(9)/l, there were 117 major bleeding episodes observed on 5.4% of the study days. In patients with no identified additional risk factors present, major haemorrhages were recorded in 0.51% (11/2147) of the study days in patients with platelet counts > or = 10 x 10(9)/l . There was a 36% reduction in platelet units transfused compared with retrospective data when an arbitrary transfusion trigger of 20 x 10(9)/l was in place (P = < 0.02). Of note, a 16% reduction in red cell transfusions was recorded. These data confirm that the introduction of a transfusion trigger of < 10 x 10(9)/l in the absence of fresh bleeding and sepsis (> 38 degrees C) is safe and has a significant impact on overall hospital transfusion costs.     

Chronic thrombocytopenia of childhood: use of non-invasive methods in clinical evaluation

OBJECTIVES: An unselected group of 21 children with chronic thrombocytopenia was investigated to understand the patients' platelet abnormality better. METHODS: Platelet counts, mean platelet volumes (MPV), membrane glycoproteins and Fcgamma receptor type IIA (FcgammaRIIA) polymorphism H131R, reticulated platelets (% RP), antiplatelet antibodies and plasma thrombopoietin (TPO) were measured. RESULTS: Sixteen patients had idiopathic thrombocytopenic purpura (ITP) (group 1: platelets < 50 x 10(9)/L, n = 6; group 2: 50-99 x 10(9)/L, n = 4; group 3: 100-149 x 10(9)/L, n = 4; group 4: splenectomised patients with normal platelet counts, n = 2). Five patients had familial thrombocytopenia. Six healthy children were studied as a reference. In the 19 thrombocytopenic patients, the platelets were significantly larger and % RP and TPO levels were significantly higher than those in the controls. Increased megakaryocytosis at diagnosis was associated with larger MPV and higher % RP but not with platelet level or TPO. The % RP was remarkably high in all ITP patients of group 1 indicating a brisk production of platelets despite low peripheral count. In all patients with familial thrombocytopenia, TPO was increased suggesting that the syndrome was not because of defective TPO production. The distribution of FcgammaRIIA alleles in the patients was similar to that in the controls. CONCLUSIONS: A combined application of % RP and TPO could be helpful in classifying patients with chronic thrombocytopenia into different categories. The observations may be of value in the clinical evaluation of ITP patients and lead to avoidance of invasive examinations at least in some patients.     

Efficacy and safety of splenectomy in adult chronic immune thrombocytopenia

For patients with adult chronic immune thrombocytopenia (ITP) splenectomy (SE) is a highly effective treatment, but there are still uncertainties regarding the long-term efficacy and safety. We evaluated the long-term efficacy and safety of SE in 48 consecutive adult patients with chronic ITP (26 women, 22 men) who underwent SE between 1990 and 2001 at the General Hospital in Vienna, Austria. All patients had no remission after steroid treatment and were steroid dependent. The median age at the time of SE was 44 years (range: 16-77 years). Of 48 patients, 37 achieved a complete remission (CR, platelet count >100 x 10(9)/l), 8 a partial remission (PR) (platelet count 30-100 x 10(9)/l), and 2 had no response (NR). The probability of the overall survival was 98% at a median postsplenectomy observation time of 3.5 years. Seven patients with CR and four patients with PR relapsed. There were no relapses after 1 year. The probability of continuous complete remission (CCR) at 10 years was 79%. The probability of having a platelet count of >100 x 10(9)/l or >30 x 10(9)/l was 61% and 67%, respectively, at 5 and 10 years after splenectomy. Of the 11 relapsed patients, 5 had a second CR ( n=3) or PR ( n=2). The postoperative platelet count was the best predictor for a long-term remission. All patients with postoperative platelet counts >250 x 10(9)/l remained in CR. Patients aged >45 years had a similar success rate as compared with younger patients. Three patients had infections (one pneumonia and two fever of unknown origin) requiring hospitalization, but none had overwhelming septicemia.     

Intramuscular anti-D immunoglobulins for home treatment of chronic immune thrombocytopenic purpura

To assess the efficacy of home treatment with intramuscular anti-D immunoglobulins (anti-D IgG) in patients with idiopathic or HIV-related chronic immune thrombocytopenic purpura (ITP), we conducted an open label, non-controlled, prospective study with a follow-up of 6 months in 51 consecutive patients with HIV-related (n = 24) or idiopathic ITP (n = 27). Anti-D IgG (13 micrograms/kg) were infused intravenously for three consecutive days (induction therapy). Patients whose platelet counts failed to increase above 50 x 10(9)/l were given a second course of the same therapy. If their platelet counts remained lower than 50 x 10(9)/l, they were considered non-responsive. Patients who responded to induction therapy were injected intramuscularly with 6 micrograms/kg/week anti-D IgG if platelets were between 50 and 100 x 10(9)/l or 13 micrograms/kg/week if they dropped to less than 50 x 10(9)/l. After induction therapy, responses occurred in 20/24 HIV-related chronic ITP patients (83%) and in 14/27 idiopathic chronic ITP patients (52%). During follow-up, platelets remained above 50 x 10(9)/l in 17/20 HIV-related chronic ITP patients (85%) and in 8/14 (57%) idiopathic chronic ITP patients. We conclude that anti-D IgG are a valid therapeutic option for treatment of idiopathic and HIV-related chronic ITP, since they are safe, cheap and can be given intramuscularly at home.     

The long-term efficacy of Helicobacter pylori eradication therapy in patients with idiopathic thrombocytopenic purpura

BACKGROUND AND AIM: A beneficial effect of Helicobacter pylori (H. pylori) eradication in patients with H. pylori-positive idiopathic thrombocytopenic purpura (ITP) has been reported by several investigators; however, it was not clear whether the recovered platelet count after H. pylori eradication was maintained for a long period. METHOD: Thirty-eight ITP patients who were examined for H. pylori infection were assessed. H. pylori-positive patients received a standard antibiotic therapy for H. pylori eradication. We investigated the long-term effect of H. pylori eradication on platelet recovery in patients with H. pylori-positive ITP. RESULTS: Of the 38 ITP patients, 26 (68.4%) were positive for H. pylori. The response rate of platelet recovery was 56.5% (13/23 patients). Twelve patients showed complete response (CR) and one showed partial response (PR). The mean platelet counts 6 months after eradication significantly increased from 31 x 10(9)/L to 129 x 10(9)/L in 23 H. pylori-eradicated patients (P < 0.001). The median platelet counts of responders 1, 2, 3, and 4 years after eradication were 168 x 10(9)/L (n = 10), 193 x 10(9)/L (n = 9), 168 x 10(9)/L (n = 7), and 243 x 10(9)/L (n = 4) after a mean follow-up of 25.8 months. CONCLUSION: Eradication therapy for H. pylori-positive patients with ITP was effective and a favorable effect was maintained for long periods.     

Platelet activation in Helicobacter pylori-associated idiopathic thrombocytopenic purpura: eradication reduces platelet activation but seldom improves platelet counts

INTRODUCTION: It has been suggested that Helicobacter pylori eradication often increases platelet counts in patients with chronic idiopathic thrombocytopenic purpura (ITP). In addition, H. pylori has been shown to induce platelet activation (CD62p or P-selectin expression) in previous studies. We assessed the response of platelet count and CD62p expression after eradication therapy in patients with ITP and H. pylori infection. METHODS AND RESULTS: We prospectively studied 15 ITP patients diagnosed with H. pylori infection by serology and breath test. A follow-up breath test was used to document eradication. Two out of 15 patients showed improvement in platelet counts after 6 months, 1 of which may have had drug-induced thrombocytopenia. Overall, certain platelet response rate in our series was 6.7% (1/15). We found that platelet CD62p expression by flow cytometry was elevated in 10/15 (66.7%) H. pylori-infected patients, which is a statistically significant difference when compared with 3/33 (9.1%) control ITP patients seronegative for H. pylori (p = 0.002). In addition, eradication therapy decreased CD62p expression (p = 0.04). However, reduction in platelet activation was not associated with an increase in platelet counts (mean 72.4 x 10(9)/l before and 68.7 after therapy; p = 0.4). CONCLUSION: In our series, platelet activation was common in ITP patients with H. pylori, and eradication therapy decreased platelet activation but seldom increased platelet counts. Increased platelet CD62p expression is a putative link between chronic infections and atherosclerosis, but further study is needed to clarify the implications of our observation.     

Efficacy and response to intravenous anti-D immunoglobulin in chronic idiopathic thrombocytopenic purpura

This review explored the effectiveness of anti-D in the management of chronic idiopathic thrombocytopenic purpura (ITP). Of 16 patients, 14 non-splenectomized and two splenectomized, with chronic ITP received anti-D immunoglobulin at a dose of 50-75 mcg/kg. A total number of 100 doses anti-D were given. Fourteen patients had previous treatment with steroids, which was discontinued either because of unresponsiveness or unacceptably high maintenance doses. Two patients had no previous treatments with any modality. Anti-D was given as a short i.v. infusion whenever platelet count dropped below 30 x 10(9)/l or patient was haemorrhagic or preoperatively. Response was defined as an absolute platelet count >30 x 10(9)/l or an increment by > or =20 x 10(9)/l. Response was obtained in 14 patients with a response rate of 87%. Fifteen patients were not on any other form of treatment at the time of anti-D therapy and one patient had a concurrent steroid therapy. The improvement in platelet count lasted for more than 8 weeks post-57% of anti-D infusions. We report two patients with previous splenectomy for ITP who responded to anti-D therapy. The side-effects profile was very mild with no patients required red cell transfusion.     

Thrombocytopenia in patients with malaria: automated analysis of optical platelet counts and platelet clumps with the Cell Dyn CD4000 analyser

Platelet counts and automated detection of platelet clumps were evaluated by optical analysis with the Abbott CD4000 analyser (Abbott Diagnostics, Santa Clara, CA, USA) in this South African study of 828 samples referred for malaria investigations. Based on microscopy (Micro) and rapid tests (RT) for HRP2 protein and parasite-associated LDH, malaria negative samples (n = 417) were defined as Micro-, RT-. Convalescent cases (n = 64) were Micro-, RT+ and had a recent record of positive microscopy. Malaria positive cases were subdivided into Micro+ (n = 315) and Micro-, RT+, PCR+ (polymerase chain reaction) (n = 32) subgroups. The mean platelet count for Micro+ cases (89.7 x 10(9)/l) was significantly lower than both the malaria negative (mean 212.6 x 10(9)/l) and convalescent malaria (mean 152.8 x 10(9)/l) groups; 89% of microscopy positive cases were thrombocytopenic (< 150 x 10(9)/l) and 30% had severe thrombocytopenia (< 50 x 10(9)/l). For comparison, 32% of the 417 malaria negative samples were thrombocytopenic and 6% of these were severe. Two thirds of samples with parasitaemia above 10% had platelet counts of < 50 x 10(9)/l while the counts were largely independent of parasite numbers when the parasitaemia was below 10%. Thirty percent of samples with microscopically detectable parasites had a PltClmp flag compared to 13% of the malaria negative group but, when the actual platelet count was taken into account, it became apparent that appearance of the flag was primarily associated with thrombocytopenia per se rather than malaria status. In most samples with a PltClmp flag, the CD4000 optical platelet clump 'signature' was indicative of small platelet aggregates and giant platelets. Morphological examination confirmed the presence of varying numbers of small platelet aggregates (3-12 individual platelets), often together with increased giant platelets, in many samples with a PltClmp flag. The observations suggest that while patients with malaria may be predisposed to the development of thrombocytopenia, a reduced platelet count in some patients may also be due in part to pseudo-thrombocytopenia.     

Comparison of thrombopoiesis during ITP and HIV-ITP and response to intravenous gammaglobulin treatment

Immune thrombocytopenic purpura's diagnosis (ITP) is based on low platelet count and exclusion of clinical conditions rather than a specific diagnostic test. We used the reticulated platelet (RP) assay to study ITP and thrombocytopenia associated with HIV infection (HIV-ITP). Data from 96 ITP and 23 HIV-ITP patients showed low platelet counts (PC) with both high or low %RP suggesting that individuals have different degrees of thrombopoiesis. About 20% of ITP and 46% of HIV-ITP patients had %RP in the 'low' or 'normal' ranges. Grouped by platelet count <30x10(9)/L, 24% ITP and 36% HIV-ITP patients had 'low' to 'normal' %RP. The patient population did not show correlation between PC and %RP, but individuals showed an inverse relationship. Within a week of receiving IVIG, 18 ITP and 9 HIV-ITP patients' PC increased, %RP decreased. Patients with %RP measured within 24 h of IVIG treatment had lower %RP than expected, suggesting dilution by an older platelet population. ITP and HIV-ITP patients' responses to i.v. gammaglobulins were similar. Thrombopoietin levels of ITP patients did not correlate with PC, %RP, or RP count. Estimation of thrombopoiesis by RP assay provides useful information for differentiation among thrombocytopenias.     

Does treatment with intermittent infusions of intravenous anti-D allow a proportion of adults with recently diagnosed immune thrombocytopenic purpura to avoid splenectomy?

This study explored whether repeated infusions of intravenous anti-D could allow adults with recently diagnosed immune thrombocytopenic purpura (ITP) who had failed an initial steroid course to postpone and ultimately avoid splenectomy. Twenty-eight Rh(+), nonsplenectomized adults with ITP diagnosed within 1 to 11 months and platelet counts 30 x 10(9)/L (30 000/microL) or below were enrolled. Anti-D was infused whenever the platelet count decreased to 30 x 10(9)/L (30 000/microL) or below. "Response" was defined as a platelet increase of more than 20 x 10(9)/L (20 000/microL) to more than 30 x 10(9)/L (30 000/microL) within 7 days of treatment. Patients were a median 3.5 months from ITP diagnosis at enrollment and had received a median of 2 previous therapies, including prednisone in 26 of 28 cases. They were followed for a median 26 months. A total of 93% responded to their initial infusion of anti-D, and 68% repeatedly responded with counts maintained above 30 x 10(9)/L (30 000/microL) using anti-D alone. Currently, 12 (43%) of 28 patients have been off all treatment for more than 6 months without undergoing splenectomy, 6 maintaining counts above 100 x 10(9)/L (100 000/microL). Seven continue on treatment, 8 underwent splenectomy, and 1 was lost to follow-up at 10 months. One patient discontinued anti-D because of toxicity. Patients with platelet counts at least 14 x 10(9)/L (14 000/microL) at enrollment were more likely to discontinue treatment (P <.05). Anti-D was an effective maintenance treatment for two thirds of Rh(+), nonsplenectomized adults with ITP who had failed an initial steroid course. Intermittent infusions of intravenous anti-D allowed more than 40% of these adults to avoid splenectomy and to achieve stable platelet counts off all therapy, even after many months of treatment. Platelet count at study entry was the primary predictor of outcome.     

High-dose intravenous immunoglobulin and splenectomy for the treatment of HIV-related immune thrombocytopenia in patients with severe haemophilia

Four patients with severe haemophilia A and one patient with severe Christmas disease developed severe immune thrombocytopenia (platelet count less than 20 x 10(9)/l). All five patients were HIV-antibody positive and one was HIV-antigen positive. Four patients were treated initially with prednisolone, but with only a transient platelet response in three and no response in the fourth. All patients were treated with high dose intravenous immunoglobulin (0.4 g/kg daily for 5 d) resulting in a rise in platelet count in all cases (range 138-300 x 10(9)/l) and then proceeded to splenectomy. Three remain in complete remission after 6-14 months, and one showed a good response with platelet counts ranging from 103 to 187 x 10(9)/l. The fifth patients achieved a normal platelet count for 3 months post-splenectomy, but suffered a relapse with platelet counts ranging from 25 to 108 x 10(9)/l over the next 3 years. However, following a severe Varicella infection 10 months ago, during which he developed a marked transient thrombocytosis, he has also maintained a normal platelet count.